Blissful innocent SpongeBob (voiced by Tom Kenny) lives at the bottom of the sea in a pineapple and works in the Krusty Krab diner run by the irrepressible Eugene Krabs (Clancy Brown).

SpongeBob dreams of becoming the manager of the sister outlet Krusty Krab II but when he rushes to the opening ceremony he's distraught to learn he has lost out on promotion to curmudgeonly Squidward Tentacles (Rodger Bumpass).

His scheme includes framing Krabs for the theft of King Neptune's priceless crown - a crime punishable by death.

Seeing a chance to redeem himself in his employer's eyes, SpongeBob ventures into the forbidden Shell City to retrieve the missing treasure, aided by his loyal but dim starfish pal Patrick (Bill Fagerbakke).

The eponymous hero is his usual effervescent self, deliriously unaware of danger; while animation throughout bubbles with bright colour.

The movie retains all of the charm and childish exuberance of the Nickelodeon cartoon series created by Stephen Hillenburg with a few surprises. The lunatic live action-animation finale, including a cameo from David Hasselhoff, is inspired.